The present invention relates to a cooler arrangement for at least one battery in a vehicle.
Hybrid vehicles powered by electricity in combination with some other form of fuel are equipped with one or more batteries for storage of electrical energy and with regulating equipment for regulating the flow of electrical energy between the battery and an electrical machine which alternately serves as motor or generator, depending on the vehicle's operating state. The battery and the regulating equipment are inevitably subject to a certain amount of warming during operation. Optimum operation of the battery and the regulating equipment depends on their not being warmed to too high a temperature. The battery must, for example, not warm above a temperature which for a certain type of battery is of the order of 40° C. The regulating equipment may warm to a somewhat higher temperature. The battery and the regulating equipment therefore need to be cooled.
Using air to cool batteries is known, but the air has to be of high quality because batteries are sensitive to pollutants and moisture. A known practice in this respect is for the battery to be situated in the passenger space of vehicles, where the air is of high quality and a fan is used to generate a cooling air flow through the battery. For various reasons, however, it is desirable for the battery to be situated elsewhere in the vehicle than in the passenger space. Another known practice is for the battery to be situated in the engine space of hybrid vehicles, in which case an air conditioning (AC) installation is used to cool the battery, since the air in the engine space is usually too warm and polluted to serve as a suitable cooling medium for the battery. Using an AC installation to cool the battery consumes a relatively large amount of energy. Since an object of hybrid vehicles is to reduce their total energy consumption, it is desirable to cool the battery in a way which consumes less energy.
US 2004/0261377 refers to a cooling device for batteries in a vehicle. In that case a fan draws air in from the surroundings into ducts whereby the air comes into contact with and cools the batteries. A specially configured inlet valve adapted to separating particles and moisture from the air which cools the batteries is used to prevent the air being accompanied by pollutants and moisture.